grounding issue

Mizzou

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So I have a tetris (conversion from an outrun cab if it matters). The g07 in it died so I figured id swap it out with a k7000 I had sitting on a shelf. I tested the k7000 to make sure it was good by hooking it up thru the back while it was sitting on a chair. Monitor checked out good. So I take the g07 out and put the k7000 in and nothing..no power to the board, no monitor power, no nothing. I accidentally touched the metal frame of the door and shocked myself...so grounding issue. I noticed the ground wasn't attached to the frame like it was on the g07 so I attached it. When I fired the game up the board would get power but no monitor power and I'd hear a loud hum....I know its something obvious, but what am i missing here....I'm getting tired of electrocuting myself lol.
 
There is an isolation tramsforner. When i was testing the k7000 it was grounded to the g07 that was still in the cab. I tried grounding it to the k7000 frame and i get the loud feedback hum.
 

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I'm not understanding. The monitor is running on the same power it was before. I just have the monitor physically in the cab now instead of hooked up in the back. Isn't this the iso tramsforner pictured below?
 

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When you tested the K7000, did you connect it to the same power connector that your G07 is using, while disconnecting your G07? It sounds like you didn't which created a hot chassis, which is why you got shocked. Your K7000 isn't working now because you probably took out some diodes and the voltage regulator and maybe other things when you grounded yourself to it.
 
Yes, the G07 was disconnected and the power from the cab that would have been going to the g07 was plugged into the k7000 instead. When I put the k7000 into the cab and turned it on, all I had hooked up was power and video, I didn't have it grounded just like it wasn't when I successfully tested it. The only physical difference I can think of is that before it was sitting outside the cab. I might have smoked something when I grounded it, but why wouldn't it have worked the first time when I put the k7000 in and tried it the first time in the cab?
 
I am not an expert on Outruns, so this could be wrong. But the schematics on arcarc say that the native Outrun transformer outputs 100V for the monitor, not 120V:


1733933831485.png



First, I would not connect any ground to the frame, if you don't know if a particular monitor uses one or not.

Second, I would take a DMM and measure the monitor power voltage, and see if it's 100 or 120V.

Also, any time you see electrical tape, someone messed with the wiring. So you can't be sure things are correct. If hot and neutral were swapped, I wonder if that could be a factor here (as normally there are safety measures in place to make SURE the metal parts of the cab don't get electrified). So something is messed up in this cab.

This is something I'd need to be in front of the cab to troubleshoot, so I'm not going to be of any more help than that. But hopefully that gives you a few threads to pull on. (And maybe someone more familiar with Outrun cabs can comment further.)
 
I am not an expert on Outruns, so this could be wrong. But the schematics on arcarc say that the native Outrun transformer outputs 100V for the monitor, not 120V:


View attachment 786724



First, I would not connect any ground to the frame, if you don't know if a particular monitor uses one or not.

Second, I would take a DMM and measure the monitor power voltage, and see if it's 100 or 120V.

Also, any time you see electrical tape, someone messed with the wiring. So you can't be sure things are correct. If hot and neutral were swapped, I wonder if that could be a factor here (as normally there are safety measures in place to make SURE the metal parts of the cab don't get electrified). So something is messed up in this cab.

This is something I'd need to be in front of the cab to troubleshoot, so I'm not going to be of any more help than that. But hopefully that gives you a few threads to pull on. (And maybe someone more familiar with Outrun cabs can comment further.)
I was thinking about the 100V output, but all Outruns I've worked on had K7000s and not Nanaos or whatever else they could've come with. a K7000 theoretically could work with just 100V but it's probably something worth looking into.

if the plug end of the power cord was replaced I would encourage opening it and verifying it wasn't wired backwards with hot to neutral/neutral to hot.

if you did run the K7000 hot as noted above I would inspect the deflection board's ground trace and see if it popped like a blown fuse, that's a hint it took a hot shot.
 
Your all going to kill me, but I mispoke, its not an outrun cab. Idk why I had it in my mind that it was. The cab has been modified/hacked to hell, but not by me. Ill have to keep looking at it and see what i can figure out.
 
Pretty sure that transformer assembly is from a gottlieb game, looks like mach 3.

Looks possible, according to this thread:


I'm also curious what cab it is. Whatever it is, it looks like the PS and wiring are original to the cab, from the way the harness and ground straps are routed. Also, it should be an easy ID, from those vent holes at the bottom front.

@Mizzou, post pics of the cab.
 
…. I might have smoked something when I grounded it, but why wouldn't it have worked the first time when I put the k7000 in and tried it the first time in the cab?
I never smoke anything if I'm working on monitors…need a clear head for that
 
Interesting. I disconnected the grounds i had hooked up and can see the board is getting power, but no picture and it is NOT playing blind...
 
You can 'see the board is getting power', but what does that mean? Just because an LED is lit, that doesn't tell you the power is correct.

MEASURE the power with a DMM. Measure the DC *and* AC voltage on all voltages (+5, +12, -5, whatever this board has). Post all values here.
 
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